CDS implementation could impact as many as 19 million ED visits annually

When the Protecting Access to Medicare Act (PAMA) of 2014 was signed into law, it included text that required physicians to consult appropriate use criteria through a clinical decision support (CDS) mechanism before ordering advanced imaging services for Medicare patients. After numerous delays, that requirement officially goes into place on Jan. 1, 2020, but what will its impact be on patient care in the emergency department (ED)? That’s precisely what the authors of a new study published in Radiology wanted to find out.

“An important first step toward preparing for PAMA implementation is the estimation of the baseline prevalence of advanced imaging orders among patients in the ED and the volume of imaging orders that would require CDS use to achieve PAMA compliance,” wrote Jahan Fahimi, MD, PhD, department of emergency medicine at the University of California, San Francisco, and colleagues. “We used the 2012–2015 National Hospital Ambulatory Care Survey to estimate the number of ED visits associated with a clinical condition targeted by PAMA and then measured the volume and proportion of these visits during which advanced imaging was performed.”

CDS must be used to order advanced imaging related to eight priority clinical areas (PCAs): coronary artery disease, suggestive pulmonary embolism, headache, hip pain, low back pain, shoulder pain, cancer of the lung, and cervical or neck pain.

Overall, the authors found that more than 26 percent of the ED patients included in the study had a reason for visit (RFV) consistent with one of those eight PCAs. Advanced imaging was used in more than 22 percent of those visits. Based on these findings, the team estimated that CDS systems focused exclusively on the eight PCAs could impact more than 6 million ED visits annually. CDS systems “covering a comprehensive list of CT imaging and MRI tests,” on the other hand, could impact more than 19 million ED visits annually.

“These estimates are reasonable approximations of current ED ordering patterns of overall advanced imaging and PAMA-related advanced imaging,” the authors wrote. “However, the actual number of patient visits will depend on the choices health care systems make, further rule making by CMS, and other trends in advanced imaging. Because implementation of this legislation is likely to substantially change current ED and hospital workflows, large numbers of providers and patients are likely to be affected.” 

Fahimi et al. also noted that some of this data was collected before CMS had approved qualified provider-led entities or CDS vendors. This could impact the accuracy of the team’s estimates. Another factor to consider, they added, is that “it remains to be seen how CDS systems are actually implemented throughout EDs in response to PAMA legislation, including how the emergency medical condition exemption will be interpreted.” And what about patients who are not Medicare beneficiaries?

“Whereas some health systems may consider narrow implementation for people who are beneficiaries of Medicare only, it is likely that the majority will opt for implementation irrespective of insurance status, and thus this should not significantly bias our estimates,” the authors wrote.